SEEPAGE FROM EARTHEN ANIMALWASTE PONDS AND LAGOONS— AN OVERVIEW OF RESEARCH RESULTS AND STATE REGULATIONS

Abstract

Wastewater seepage from earthen animal waste lagoons and storage ponds can contaminate groundwater withnutrients and pathogens. For almost 30 years, the subject has been the focus of laboratory and field research projectsdesigned to (1) measure if and how much earthen ponds and lagoons leak, (2) determine how different soil types affectseepage rates, and (3) evaluate the magnitudes and mechanisms of sealing from animal waste. In this article we present aresearch review performed to determine how researchers have attempted to answer these questions and how well theyhave been answered. We discuss weaknesses in the body of knowledge and present further research and educationalneeds. We also performed a review of 14 state regulations to assess and compare how different states govern seepage fromponds and lagoons. Six states regulate the maximum allowable seepage rate from ponds and lagoons (values ranging from0.042 to 0.63 cm/day) while another six states regulate the maximum hydraulic conductivity of earthen liners (valuesranging from 0.086 to 0.0086 cm/day). The two remaining states regulate neither. The results of this research andregulatory review demonstrate that there is still much to be learned about seepage from animal waste ponds and lagoons.We suggest that a risk-based approach to regulating seepage may be appropriate in the future.